1. Field of the Invention
The present invention relates to a content storage control apparatus controlling the operations of recording and playback of broadcast programs (hereinafter referred to as “programs”) and to a control method therefor.
2. Description of the Related Art
In recent years, broadcast receivers, PCs, and other equipment offering users the ability to connect to the Internet and browse Web pages etc. in addition to the features of broadcast wave reception and program viewing, has become increasingly common. Moreover, broadcasting companies and telecommunications carriers have discussed and proposed a variety of ideas related to merging broadcasting with telecommunications and it would not be hard to imagine that in the near future viewers will enjoy broadcasting services and telecommunication services seamlessly.
When a broadcast wave is viewed in real time in such a broadcast reception environment, for example, the use of URL information transmitted by broadcasting stations as additional information separately from video and audio allows users to enjoy services such as browsing Web pages associated with a program.
However, when a program was recorded in the past, such additional information was not recorded and, as a result, when the recorded program was viewed, it was impossible to use the URL information provided when the program was broadcast.
A technology permitting acquisition of URL information for Web pages (associated Web pages) associated with a program when a recorded program is played back has been disclosed in Japanese Patent Laid-Open No. 2002-215924, although in this case, the URL information is not provided by a broadcasting station when the program is broadcast. As described in Japanese Patent Laid-Open No. 2002-215924, when a program recorded by a user computer is played back, the computer accesses a program information-providing server, which stores URL information in association with program titles, and acquires the URL information corresponding to the program being played back. As a result, the user can check associated Web pages provided by the server during the playback of the recorded program.
However, the method described in Japanese Patent Laid-Open No. 2002-215924 requires the use of a separate server for providing program-related information. Furthermore, in addition to the fact that it is necessary to access the server during the playback of the program, no information is obtained regarding programs not registered on the server. Furthermore, information related to associated Web pages is still not included in the recorded data. For this reason, it is impossible, for instance, to obtain information on associated Web pages provided by a broadcasting station when the program is broadcast or Web pages that have been associated with the program by the user.
On the other hand, the use of URL addresses corresponding to programs scheduled for recording for the purpose of downloading reference data corresponding to the programs from the Web is disclosed in Japanese Patent Laid-Open No. 2002-94887. In addition, it is disclosed that the downloaded reference data and recorded programs are retained in association with one another and the reference data are also displayed when playing back the programs.
In Japanese Patent Laid-Open No. 2002-94887, the object is to download the reference data prior to the recording of the programs, that is, before the programs are broadcasted. In other words, the reference data is acquired once and stored. However, in actual practice, the content of the Web pages associated with a program is in many cases updated during the program is being broadcast. For instance, in some cases the content of the Web pages is updated as the program progresses. In such cases, there is a chance that the content of the stored associated Web pages displayed in parallel with playback when the recorded program is played back may not match the content of the program being played back if the reference data is acquired only once prior to the broadcast of the program, as described in Japanese Patent Laid-Open No. 2002-94887.
Furthermore, a method involving storing a TV program and web content corresponding to the TV program in a PVR and displaying the stored web content in sync with the playback of the stored TV program is disclosed in Japanese Patent Laid-Open (Tokuhyo) No. 2004-529588. In addition, as is disclosed in Japanese Patent Laid-Open (Tokuhyo) No. 2004-529588, a time stamp is appended to the stored TV programs and web content and, during program playback, the web content that has the same time stamps is read from the memory in accordance with the time stamps of the TV program. Also, as taught in Japanese Patent Laid-Open (Tokuhyo) No. 2004-529588, when a TV program is recorded, the web content is acquired more than once.
Japanese Patent Laid-Open (Tokuhyo) No. 2004-529588, however, makes no disclosure as to associating the acquisition of the web content with the updating of the web content itself. Namely, in accordance with the technique disclosed in Japanese Patent Laid-Open (Tokuhyo) No. 2004-529588, the content is downloaded and stored in the PVR on a constant basis even if there have been no updates to the web content itself. In other words, absolutely the same content may be stored multiple times, thereby lessening the storage capacity of the PVR.